“Greenhouse gases are constantly being added to and subtracted from the atmosphere by natural processes,” Denniston told Newsweek. “Human activity has profoundly interfered with these systems. When we burn fossil fuels, we are taking carbon that was slowly pulled out of the air over millions of years and stored in the ground as coal and oil, and pumping it back to the atmosphere in a geologic blink of an eye. This causes the atmosphere to warm, which causes all sorts of side effects.”

Denniston has dedicated years to studying and researching climate change and the environment.